For example, a vehicle such as an automobile is equipped with an exhaust gas purification device for purifying exhaust gas generated in an internal combustion engine. The exhaust gas purification device includes a temperature sensor that detects the temperature of exhaust gas, and performs control on the basis of the temperature detected by the temperature sensor so as to reduce exhaust emissions.
The temperature sensor for use in the exhaust gas purification device is exemplified in Patent Literature 1. The temperature sensor of Patent Literature 1 includes a temperature-sensing element for detecting temperature, a pair of element electrode wires extending from the temperature-sensing element, and a pair of lead wires electrically connected to the pair of element electrode wires. Each of the element electrode wires is made of a Pt (platinum)-based alloy containing strontium, and formed in a rod-like shape. Each of the lead wires is made of a stainless alloy, and formed in a rod-like shape. The pair of element electrode wires and the pair of lead wires are bonded to each other by being welded together in such a manner that they overlap each other in the direction orthogonal to the axial direction thereof.